Because of the ever stricter emission limiting values for motor vehicles, they typically have a so-called tank venting device. The core of the tank venting device is a fuel vapor accumulator, which may be implemented as an activated carbon container, for example. The fuel vapors escaping from the fuel tank are supplied to the activated carbon container via a connection line and absorbed therein by the activated carbon. The activated carbon container is also connected via a venting line to the intake manifold of an internal combustion engine of the motor vehicle, a tank venting valve being situated in the venting line. The activated carbon container is regenerated in specific operating states of the internal combustion engine, in that the tank venting valve is opened and the absorbed fuel vapors are thus supplied via the intake manifold to the internal combustion engine and participate in the combustion therein. The activated carbon container may also be connected to the surroundings via a ventilation line and a ventilation valve situated therein. During a tank venting procedure, the ventilation valve is opened to achieve a flushing effect.
A tank venting device according to the preamble of claim 1 is known from U.S. Pat. No. 5,056,494.